1. Field of the Invention
The present invention relates to ophthalmological apparatuses.
2. Description of the Related Art
Conventionally, as a technique for measuring ocular correction data, measurement of S (Sphere), C (Cylinder) and A (axis) by a refractometer has been carried out. Besides, recently, an eye characteristic measuring apparatus capable of measuring higher order aberrations has also been developed, and not only S, C and A on a line like, for example, a ring of φ3 mm as in a refractometer, but also S, C and A on a plane when a pupil diameter is made various sizes can be calculated from lower order aberrations. By the eye characteristic measuring apparatus like this, especially after a refraction correcting surgical operation or in an eye disease, values closer to prescription values of eyeglasses or contact lenses than the refractometer can be calculated (for example, see Patent document 1-4 described followings etc.).
Apparatuses for displaying how a person under examination sees with a corrected eye or a naked eye have also been disclosed by the present applicant (in patent documents 5 and 6). In these apparatuses, for example, how a predetermined eyesight-test target is seen is displayed on display means according to the optical characteristics of an eye under measurement.    Patent document 1: Japanese Unexamined Patent Application Publication No. 2002-204785    Patent document 2: Japanese Unexamined Patent Application Publication No. 2002-209854    Patent document 3: Japanese Unexamined Patent Application Publication No. 2002-306416    Patent document 4: Japanese Unexamined Patent Application Publication No. 2002-306417    Patent document 5: Japanese Unexamined Patent Application Publication No. 2001-120504    Patent document 6: Japanese Unexamined Patent Application Publication No. Hei-7-100107
There have already been apparatuses capable of measuring eye aberration, as described above, and aberration measurement can be performed even when a contact lens is worn. How an eye under measurement sees have been evaluated by simulating a retinal image with the use of obtained aberration. In general, a point spread function (PSF) includes wavefront aberration and a scattering component. When the center of gravity of each spot is detected from a Hartmann image, only wavefront aberration is obtained even if scattering occurs.
In some cases, a stain on a contact lens, and the deterioration and dryness thereof largely affect how an eye under measurement sees, and if only the effect of aberration is taken into consideration, the measurement result is far away from how the eye under measurement actually sees. More specifically, if a Hartmann image blurs due to scattering caused by a stain on a contact lens, aberration does not change unless the center of gravity is changed, in wavefront aberration measurement which uses the Hartmann image. However, this scattering largely affects how the eye under measurement actually sees.